System including rotary blades



Da 31, 1940- R. PATERAS PESCARA 2,226,978

SYSTEM INCLUDING ROTARY BLADES Filed Feb. 6, 1935 '7 Sheets-#Sheet` l ,lMM5/vra R.- Muz Part/ms Pfscnxn Dec- 31, 1940; R. PAU-:RAS PESCARA2,226,978

SYSTEM INCLUDING ROTARY BLADES 'Filed Feb. 6, 1935 7 Sheets-Sheet 2/m/f/vra/f:

ma fn 7504s Pesca/Mz' Dc. 31, 1940. R. PATERAs PESCARA 2,226,978

SYSTEM INCLUDING ROTARY BLADES Filed Feb. 6, 1955 7 Sheets-Sheet 3/Nl/E/VTO.'

RAUL PA TER/IIS 'PESCA/ffii De- 3l, l940- R. PATERAS PESCARA 2,225,978

/SYSTEM INCLUDING ROTARY BLADES Filed Feb. 6, 1935 7 Sheets-Sheet 4 2.9by @man Dec'. 31, 1940.

R. 'PATERAS PESCARA 2,226,978

SYSTEM INCLUDING ROTARY BLADES Filed Feb. e, 1935 7 sheets-sheet 5 DeC.31, PATERAS PESQQBA sYs'rEM INCLUDING ROTARY BLADES Filed Feb. 6, 193s''sheets-sheet e /NI/f/V TUR.' y? @Al/L PTEA PESCA RA 1 D- 31, 1940 R.PATERAs PESCARA 2,226,978v

SYTEM INCLUDING ROTARY BLADES' Filed Feb. 6, 1935 '7 Sheets-Sheet 7 lIN1/avrai? @A L PA ffm; fasc/1 HA .f

Patented Dec. 31, 1940 PATENT OFFICE SYSTEM INCLUDING ROTARY BLADES RaulPateras Pescara, Paris, France Application February 6, 1935, Serial No.5,260 In France February 6, 1934 37 Claims.A (Cl. 244-6) The presentinvention relates to systems including 'rotary blades such as supportingsystems, propelling systems, power generating systems (wind engines),etc., and it is more especially, al-

though not exclusively, concerned with systems of this kind for use inconnection with aircrafts. The object of the present invention is`toprovide a system of the kind above referred to which Iis better adaptedto meet the requirements of current practice than systems of this kindused up to this time, especially with a view to reducing the fatigue 'ofthe structural elements of the system (due to bending and torsionalstresses) l and to improving the efficiency and the range of adaptationof machines or apparatus including systems of this kind. n The essentialfeature of the present invention consists in constituting the blades ofthese systems, and especially the rotary wings of some types of yingmachines, with elements which are wholly supple in the direction oftheir length, and along at leasta portion of said length, said elementsbeing adapted to become rigid, when rotating, in a position ofequilibrium determined by the combined action of the centrifugal forcesi and of the aerodynamic forces.

Another feature of the present invention consists in making use of thesupple structure of said blades for making it possible to vary at willtheir active length, and consequently the area swept over by saidblades. This result is obtained through suitable means permitting forinstance to wind or unwind the blades, or again to fold or unfold them.Advantageously, in thecase of the bladesbeing used in connection withaircrafts, the blades or variable area thus constituted are combinedwith stationary supporting surfaces.

Another feature of the present invention consists in combining4 withsaid blades means for varying at will their inclination with respect tothe plane in which they rotate.

Still another feature of the invention consists in providing said bladeswith a frame consistin substantially of a system of cables.

Finallyfstill another feature of the invention consists in constitutingthese supple blades of a 5o fluidtight envelope capable of being maderigid,

at least in the transverse direction, by the presy sure of a gaswhicheither -lls the space inside said envelope or -flows ina continuousmanner through said space.

- .5 Y Other .features of the present invention will result from thefollowing detailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafterdescribed with reference to the accompanying drawings, given merely by 5way of example, and in which:

Fig. 1 is an elevational view of a thin blade for rotary aircraft wingsmade according to the present invention;

Figs. 2 and 3 are a plane viewand a cross secl0 tional view,respectively, of the blade shown in Fig. 1;

Fig. 4 is a cross sectional view of a thick blade made according to thepresent invention;

. Fig. 5 is a plan view corresponding to Fig, 4; 15

Fig. 6 is a cross sectional viewof a blade of the same kind madeaccording to another embodiment; V

Fig. 7 is a plan view of the blade shown in Fig. 6; 20

Fig. 8 is a cross sectional view of a blade adapted to be inflated bymeans of air, according to the present invention; l

Fig. 9. is a plan view of the blade shown in Fig. s; 25

Fig. 10 is a cross sectional View of a blade made according to amodification of the embodiment of Figs. 8 and 9;

Fig. 11 is a longitudinal sectional view of the combination of a bladeof the kind of that shown by Fig. 10 with a device for carrying andinflating said blade, according to the present invention;

Fig. 12 is a diagrammatic sectional view of the combination of a rotarywing system having supple blades, its hub, and means for permitting tovary the length of said blades, according to the present invention;

Fig. 13 is also a sectional view showing a combination of the same kind,in the case of thick 4 0 blades, according to another embodiment of theinvention;

Fig.14 is an axial sectional view of a device of the same kind madeaccording to another embodiment of the invention;

Fig. 15 is a plan view corresponding to Fig. 14;

Fig. 16 wis a partial side view of an organ of the combination of Figs.14 and 15; y

Fig. 17 is a diagrammatic sectional view of a device for folding up andiniiatng a blade of the kindof that shown by Fig. 10;

Fig. 18 is a cross sectional view of a foldable blade of the same type,corresponding to another embodiment;

Fig. 18 is a Partial longitudinal section of e155 combination of a bladeof the same type with a device for folding up and inating the bladesmade according to another embodiment;

Fig. 20 is a sectional view of a supple blade which can be given avariable angle of incidence, according to the present invention;

Fig. 21 shows, in section through the axis of a system of rotary wingshaving supple blades, a device for twisting the blades, according to theinvention;

Fig. 22 is an elevational view of an airplane according to the presentinvention including fixed wings and rotary wings having supple andexpansible blades;

Fig. 23 is a side view corresponding to Fig. 22;

Figs. 24 and 25 are views, similar to Figs. 22 and 23 respectively, ofanother embodiment;

Fig. 26 is a side View of an airplane the cabin of which can bedetached', made according to the present invention;

Fig. 27 is a plan View of the airplane shown by Fig. 26.

The invention is especially applicable to flying machines provided withrotary blades, said blades being either driven in a` continuous mannerbyv an engine (case of helicopters) or by reaction, or turning freelyunder the action of the relative wind (case of gyroplanes); But theinvention should not be considered as limited to this type of machines.

It should rst be noted that a system of wings of the type above referredto made according to known principles has the disadvantage of having itsstructural elements subjected to bending stresses which are particularlydangerous because their alternation may produce the crystallization ofthe materials or set up a resonance capable of breaking the blades.

An important improvement, described in Spanish Patent No. 65,076, 4hasbeen provided for systems of wings of the kind above mentioned. Thisimprovement consists in pivotally connecting the blades to their hub insuch manner as to leave them free to assume the position of equilibriumresulting from the combined actions of the centrifugal and aerodynamicforces `on said blades. Although the bending stresses are thusconsider-A ably reduced, since the blades are free to assume variablerelative positions, these stresses are not wholly eliminated, because ofthe rigidity of the blades.

According to the present invention, and especially in order to obviatethe drawbacks that have been just above mentioned, the blades of thesystems of wings are made of elements which are fully supple (and notonly flexible) in the direction of their length and along at least aportion of said length, said elements being adapted to become rigid,when revolving, in a positionA of equilibrium, under the action of thecentrifugal and aerodynamic forces.

Preferably, and as it will be assumed in the following description, saidelements areV so de- .vised as to be fully supple, so as to obtain, whenthe blades are revolving, not only a general equilibrium but anelementary equilibrium, said equilibrium being determined merely by theexternal forces (centrifugal force and aerodynamic force) and by thetensile forces, anyl bending stresses being eliminated.

Il have found that, in order to make a blade which complies with theseconditions, it is advantageous to make use of a structure including, onthe one hand a frame which is more especially 75 intended to resist thetensile stresses that balance the action of the external forces, and, onthe other hand, an envelope, also supple, which is supported by saidframework, and which is given a suitable shape according to the desiredcross sectional shape of the blade when the latter is working.

However, it should be well understood that this arrangement is not anecessary feature of the present invention which also includes the casein which the framework and its envelope would be made as a single pieceof a suitable supple material capable of resisting in a satisfactorymanner the tensile stresses. v

According to the first mentioned embodiment, the framework consists, forinstance of at least one set of cables l (eventually several such sets),

preferable made of metal. It should be noted that the word cable is tobe taken in its most general meaning, including bands, ribbons, wires,etc.

'I'his system of cables is so devised that cables l are fixed at oneen'd, on the side nearest to the axis Il about which the rotary bladesare pivoted, to a corresponding piece or part 2 of the hub of saidblades.

These cables I run in the direction of the length of the blade and aredisposed, for instance, either radially with respect to axis 0 (Figs. 1and 2), or parallelly to one another (other figures) In this way Iobtain a system which, even if considered independently of the envelopewhich will be hereinafter described, is subjected, in the rotarymovement of the blade, to the action of the centrifugal force, due toits own weight, and therefore tends to assume a position of equilibriumaway from axis 0.

Of course means are provided for giving this structure a suitablerigidity.

These means may, for instance, merely include a rigid or semi-rigidpiece 3 extending transversely yto said cables l and to which the freeends of said cables are flxed, said ypiece being preferably madeheavyenough in order that the centrifugal force it develops may be added tothat resulting from the weight of the set of cables l (Figs. 2, 5, 7 and9). Eventually, I may x to said piece 3 only 'the extreme cables of thesystem of cables, as shown by Fig. 7.

But it may be advantageous -to further increase the ltransverse rigidityof the framework.

For this purpose I may, according to an embodiment not shown in thedrawings, provide along the blade one or several ribs vsimilar to piece3, which serve to connect the different cables together.

I lmay also provide transverse cables 4 along cablesI l, in which caset'he framework consists of a kind of trellis-work structure. It may evenconsist of a metal cloth or fabric.

Any structure increasing rigidity in the transverse direction of theblade without reducing suppleness in the longitudinal direction may beemployed.

The'envelope to be carried by this framework may be made in differentways.l

to provide, along lthe leading edge and the traiiing edge of the blade,elements I and 9 arranged to give said edges the desired shape, saidelements being supple in the longitudinal direction and having a certainrigidity in the transverse direction. made of a stiff fabric orindia-rubber and they are eventually reinforced by cables such as 9. Thespace between the upper and under faces of the blade is filled with amatter 6 which is both plastic and iight, such for instance vassponge-like rubber. This matter bears, at the free end of the blade,against transverse piece 3, which will thus support most, or even thewhole, of the resultant of the centrifugal forces acting on said matter6, and will transmit it to the system of cables I.

Advantageously, this filling material 6 will be engaged in grooves I0.provided in elements 'I and 8.

In .the case of a thick blade of this kind, the framework may consisteither of a single system of cables provided either ,along the upperface ofthe blade or along the under face thereof, or of two sets ofcables disposed along said faces of the blade, respectively. But mydevice is not limited to these arrangements.

According to another embodiment, which is particularly advantageous, Iprovide an envelope II (Figs. 8 to 1l) made of a iluidtight supplematerial, either coated-with varnish or not, such for instance asrubberized cloth, inside which a certain gas pressure is ensured.

For this4 purpose, a certain amount of gas, air for instance, isenclosed at a suitable initial pressure in said envelope which is to beso devised as to prevent any leakage of air (Figs. 8 and 9).

Alternately, air is causedto flow in a continuous manner through theenvelope, said air being, for instance fed from the hub and issuingthrough at least one nozzle I2 which is suitably positioned (Figs. 10and 11) This gas pressure will give the blade the necessary transverserigidity, eventually in combination with framework I, which may beeither fixed to said envelope, or free with respect thereto, bothelements (the framework and the envelope) being preferably, in eithercase, fixed to piece 3. Furthermore, the framework may be disposedeither on the inside of theenvelope, or, as shown in Figs. 8 and 10 onthe outside thereof, advantageously against the upper or the under facethereof, so as to leave the inside of the blade wholly unobstructed andnot to brake the flow of air, when air ows throughout the blade.

Finally, the framework may be wholly surrounded by a suitable matter 6.

When air is caused to flow continuously throughout the blade, the piecethat carries .the blade may consist of a hollow cylinder 2 to which airis fed from a source of pressure provided in the aircraft. The cables I,on the one hand, and the envelope, on the other hand, are fixed to saidcylinder. Air is admittd into the blade 'through openings I3 provided insaid cylinder,

and itgescapes from said blade through any suitable otlet means, forinstance nozzle I2 (Fig. 11). Finally, whatever be the specificstructure of Y the blade, the .whole 4is so devised, or means are 0 soarranged, that saidblade has a suitable angle of incidence whenrevolving. This result can be obtained in various ways. For instance Imay provide on some elements, and es-pecially on the leading andtrailing edges of the blades, one or 75 several masses fixed either atintermediatepoints Elements 'I and 8 are for instanceA of the length ofthe blade or at the end thereof, said masses being so arranged andcalculated that the centrifugal forces acting thereon tend to give theIblade a suitable relative position and,`

at the same time, to increase the rigidity thereof.

With an arrangement such as above described, when no'force is acting onthe blades, as the latter are fully supple, they can be folded up in anysuitable manner, and eventually they may be fixed in a position of restthrough any suitable means. As soon as the blades are caused to revolve,they are moved away from the axis of revolution and they tend to becomerigid in a position of equilibrium, under the combined actionsl of thecentrifugal and aerodynamic forces.

A system of wings of this kind possesses, over the usual systems ofwings used, for instance in gyroplanes and helicopters, up to this timemany advantages, and especially'that of eliminating any bendingstresses. l

The advantages obtained according to the present invention as abovedescribed are considerably increased when use is further made of thearrangements that will be hereinafter described andl which are intendedto increase the eihciency and the possibilities of use of rotary bladessystems of the kind above mentioned (whatever be their application). Inparticular when said systems are used in aviation the arrangements thatwill .be hereinafter described make it possible to create new types ofapparatus which can be given high vspeeds of translation while keepingthe advantage of taking off or landing vertically or obliquely atrelatively low speeds. Furthermore the space occupied by these apparatuswhen not in use are considerably reduced.

In existing flying machines the supporting surfaces of which consist of,or include, rotary blades, the latter permit of improving the conditionsunder which the machines take oif or land, provided that the area sweptover by said blades is considerable. But when the machine is flyingnormally, the area swept by the revolving blades is much too large,which-brakes the flying machine. It follows that, up to the presenttime, machines of this kind could not fly at high speeds.

The ratio of lift and drag with supporting surfaces of this kind isalways rather bad and consequently these systems are not very widelyused, despite the undeniable advantages theyV possess from the point ofView of easy taking off and landing and safety in flight.

On the other hand, with fixed supporting surfaces the best ratio of thecomponents above mentioned is always higher than with revolvingsupporting surfaces, but, in the case of ying machines provided withsaid fixed supporting surf-aces, these high ratios (which correspond toloads per square meter of supporting area as high as several hundreds ofkilogrammes) cannot usually be taken advantage of, in view of thedifliculty of taking off and landing, or because they would make itimpossible to reach high altitudes.

Furthermore, the systems of revolving blades existing at the presenttime, whatever be their applications, are not, as a rule capable ofadapting themselves to variations' of velocity and density of the mediumin which they are moving or the velocity of which they are utilizing.

-In order to obviate these drawbacks, according to the presentinvention, the systems of revolving blades or wings consist of suppleblades of the kind above described. Furthermore these blades are soconnected to their hub that it is possible to vary their active surface,and consequently the area swept over by said blades,

i within wide limits, and, if need be, between zero and a maximum area.This variation is performed either automatically or manually, either asa, function, for instance, ofthe velocity of the wind in the case ofWind engines, or as a function of the speed of relative movement, in thecase of revolving blades for fiyingvmachines, as it will be hereinafterassumed.

In order to obtain this result I may cause a portion of variable lengthof said blades to be pulled inside the hub of the system of revolvingblades, for instance as shown in Fig. 12.

I may also provide said hub with drums about which can b e wound up orunwound said blades, that is to'saythe whole of their framework andtheir envelope (Fig. 19).

Both -of these devices may also be combined, the envelope of thebladebeing for instance pulled inside the hub while the framework isWound or unwound around a drum (Figs. 13 and 17).

Both of these elements, envelope and framework might also be woundor`unwound around different drums respectively.

Furthermore, according to a particularly advantageous arrangement, thefolding or unfolding of the blades is controlled in such manner as to beproduced by the revolving movement of said blades themselves.

With this arrangement, the unfolding of t-he vblades preferably takesplace under the effect of the centrifugal force acting on said bladesand tending to pull them outwardly. The folding or winding up of theblades takes place through means for combining` this movement with therotary movement of the hub or rotor that carries said blades, throughthe medium of organs acting directly on the blades for performing themovement.

According to a first embodiment shown in Fig. 12, the hub I4 of thesystem, which is made hollow and which is journalled in stationary partsof said system, for instance through ball bearings I5, carries twoblades P disposed in opposed relation with respect to each other andconstituted by the same ribbon or band. This ribbon or band is caused topass on the one hand around drums I6 carried by said hub, and, on theother hand, around a. pulley I1 movable in the vertical direction insidethe hub.

Said pulley is for instance carried by a sup porting member I8 securedat the end of cable I9. Cable I9 is adapted to wind -or unwind on a drum20 carried by a stationary part of the machine. This drum 20 can bedriven either manually, through a suitable speed reducing gear includingeventually a pawl or the equivalent, or through a motor which, as abovestated, may consist of the rotoritself.

Between member I8, which turns together with the hub or rotor, and cableI9, there is interposed, for instance, a ball bearing 2|.

This device has two disadvantages: First the hub must be relatively high(its height being at least equal to the length of the portion of theblade that is to be pulled in inside said hub; secondly the hub issubjected to a strong compression equal to the sum of the centrifugalforces acting on the blades.

These drawbacks may be obviated by making use of a device of the kind ofthat shownby Fig. 13. In this embodiment each blade is secured to thehub at 22 and it is caused to pass either around a single pulley IImounted in the same manner as pulley II of the preceding embodiment, oraround the pulleys of a pulley block. In this case, the displacement ofcable I9 is smaller than the corresponding longitudinal displacement ofthe blades (one-half thereof with the arrangement of Fig. 13).

` The various pulleys Il corresponding to the respective blades may becarried by a common support I8.

In Fig. 13 it has been assumed that the blades had a relatively thickoutline or cross section, and that the framework of said blades waswound around drums 23, controlled in any suitable manner, independentlyof the envelope or body of the blade which is caused to pass aroundpulleys I'I. For instance, the framework of each blade is advantageouslydisposed on the outside of the body of said blade, as it will behereinafter explained with reference to Fig. 18).

If these thick blades are provided with a filling material, for'instanceas above described with reference to Figs. 4 and 5, it may be advantageous to impose on said material a certain tension which cannot belsupplied by the centrifugal force since said material butts againstpiece 3. Accordingly, I provide a connection between drums 23, aroundwhich the frameworks are wound, and movable member I8. This connection,for instance, is constituted by cables 24, which are fixed to saidmember I8 at one end, are wound around pulleys 25 carried, through ballbearings 26, by a support 21 subjected to the tension of a spring 2Isecured to a stationary part of the machine, andare finally fixed, attheir other ends to theperipheries or pulleys rigidly xed to drums 23,in coaxial relation therewith, the last mentioned pulleys having adiameter equal to one half the diameter of drums 23.

In Figs. 14 to 16 I have shown an embodiment according to which blades Pcan be wound or unwound on respective drums 29 the spindles of which arejournalled in aframe 30 integral or rigid with rotor 3I.

In order to either permit said drums to turn freely so as to produce theunfolding of the blades under the effect of the centrifugal force, orcause said drum to turn in the reverse direction so as to wind up theblades, I make use of a device including a member, disposed preferablyin coaxial relation with respect tothe rotor and adapted to beconnected, through suitable gears with the drums above referred to.

Said member is so devised as to be capable of:

(a) Either turning freely about its axis, in which case the drums canturn freely in their frame under the effect of the centrifugal forceacting on the blades, which produces the unwinding of said blades;

(b) Or being immobilized, in which case a rotary movement is transmittedto the drums in the direction that causes the blades to be wound uparound ,said drums;

(c) Or finally being driven together with the rotor in which case thedrums are prevented from turning about their spindles and the bladesremain in the position they have been given.

An embodiment of such an arrangement is shown in Figs. 14 to 16. Themember above referred to consists of a sleeve 32 disposed between rotor3I and a hollow shaft 33 fixed on the machine and carrying the whole.

This sleeve 32 can either turn freely about its axis, or be fixed toshaft 33 through a clutch 34, or finally be driven by the rotor, forinstance through a system of sliding dogs, some of which 351 are carriedby sleeve 32, while the others 352 are carried by a member 36 which isarranged to rotate together with the rotor and is capable of slidingwith respect thereto.

The movement of said sleeve 32 is connected to that of each of the drums29 through pinions 31 and 38 fixed in coaxial relation with each other.Pinions 31 mesh with toothed wheels 39 rigidly carried by the spindlesof the respective drums, while pinions 40 mesh with a toothed wheel 40integral with the top of sleeve 32.

Rotor 3l is driven through any suitable means, for instance through ashaft 4l andigears 42, 43, and 44. Preferably, this device is completedby means such' that when the winding up of the blades is finished drums29 are automatically stopped.

These means are for instance so devised that, during the winding up ofthe blades, sliding meml ber 36 is locked in a position in which dogs351,

352 are not in engagement with one another.

For instance a pin 45, carried by rotor 3l and adapted to pass through aslot 46 provided in member 36, carries a head 451 of larger widthcapable, inthe aforesaid position, of entering a correspondingly widenedportion 41 of sleeve 46.

Furthermore, the unlocking can be automatically obtained through meansmovable under the effect of the relative rotary movement of rotor v 3|with respect to sleeve 32, which is stationary during the winding up ofthe blades, member 36 then coming back, under the action of a spring 48,toward a position in which said dogs are operatively engaged with oneanother.

'Ihese last mentioned means consist for instance of a nut 49 screwingupon a threaded portion of the outer periphery of sleeve 32 and adaptedto slide in a ,groove 56 providedin rotor 3 I. At the end of the windingup, said nut pushes an inner projection carried by pin (which is movablewith respect to the rotor in a radial direction against the action of aspring 5I Therefore the head 451 of said pin is pushed out from vitshousing 41 and member 36 is released and can slide under the action ofits spring 48.

The control of clutch 34 (which has been diagrammatically shown in thedrawings and may be of any suitable type) and of sliding member 36, orin a general manner the control of any similar organs permitting toobtain the unwinding or the windingup of the blades may be eithermanual, as shown in Fig. 14, or automatic, depending in this case ofcertain conditions of working of the machine, for instance the speedthereof or the speed of revolution of the rotor. It may also be sodevised as to be at will either manual or automatic.

A manual control will advantageously include (Fig. 14) a single lever52, capable of acting both 4on member 36 and on clutch 34. For instancesaid lever is adapted to act on member 36 can engage, said catch beingrigid with a sliding handle 58 carried by lever 52.

Said lever 52 acts on the clutch- 54 through any suitable means (notshown in the drawings) act-V ing against the action of a spring 59connected to lever 52 through a rod 66.

This device works in the following manner:

In order to cause the blades to be unwound, lever 52 is brought intoposition C for which, on the one hand, dogs 351 and 352 are not inengagement with one another and, on the other hand, sleeve 32 is notoperatively connected with any of the parts. The centrifugal forcecauses the blades to unwind. In order to stop this movement it willsuffice to release lever 52. This lever is then brought back intoposition A under the action of spring 48 of member 36, said member 36being itself brought back into the' position in which dogs 351 and 352engage one another.

In order to wind up the blades, lever 52 is brought into position B,catch 51 being engaged with the edge of spring 56. In this positionmember 36 is fixed in position by means of its pinv 445 and sleeve 32 isimmobilized.

The blades are then wound up on their respective drums and nut 49 movestoward said pin 45 until it comes into contact with the inner headthereof, thus producing the unlocking ofmember 36. Said member issuddenly brought into the position thereof that corresponds to theengagement of the respective dogs 351 and 352 together. In the course ofthis movement, spring 56 is deformed and releases handle 56 so thatlever 52 automatically comes back into position A, which is xed by astop 6I. v

The various devices above described would also apply the, thick wingsinflated with air of the kind of those described in the first part ofthis specification. In this case, means must be provided for permittingthe injection of air into the blades in combination with the means forwinding up or unwinding the blades.

For instance, as shown in Fig. 19, if the blades are wound up arounddrums 29, I may provide in each drum 29 orifices 290 suitably disposed,the ends of the envelope being fixed in a iiuid tight manner yto saiddrum.

A similar arrangement may be employed may be used when frameworks l arewound around drums 23 independently of the envelope, as shown forinstance in Figs. 1'1 and 18.

According to'this embodiment air under pressure is fed into a fluidtightbox 62 through which at least one blade can pass in a fluidtight manner,said box containing the corresponding drum or drums 23. Air can enterthe envelope of the blade, while the latter is passing inside box 62, bymeans of openings 63 provided in said envelope, said openings beingsubsequently stopped in a fiuidtight manner by the framework, which isapplied with a fluidtight iitagainst the outer face of said envelope.

' The blade enters and leaves box 62 through packing means 64 and 65preventing the compressed air in said box from escaping past the wallsof said box. On the side of the hub, the envelope passes between twodeformable rollers 66 pushed toward each other by springs 61.

Advantageously, framework I carries a suitable plastic material 6providedv with a band `of a compressible material'69 (Fig. 18) soarranged that said band is applied against openings 63 of the envelopeand stops said openings.

Furthermore, the blade, when issuing from box 62, is caused to passbetween rollers 69.

In order to have the framework l to fit against the envelope with asufficient amount of safety,` said envelope is advantageously provided,along the edges of the housing 10 that isto receive the But I believethat it is much more advantageous to provide flying machines of a newkind characterized in that they include, on the one hand, a stationarysupporting surface, which, preferably, cannot be varied, and, on theotherhand,

a supporting system of variable area, consisting of a system ofrevolving blades of the kind above described.

This arrangement would permit of obtaining for any particular conditionof flying the best possible adjustment. For flying at high speed, themachine would be wholly, or nearly wholly, supported by the fixedsurfaces used with the best possible angle of incidence, the blades ofthe revolving system being then partly or wholly folded up or wound upso asto produce but very little resistance.

On the contrary, when taking off or landing, either vertically orobliquely, the machine would be-supported chiefly by the system ofrevolving blades, so as to permit of obtaining very small vertical oroblique speeds, the blades being then unwound or unfolded to the maximumamount possible.v

For intermediate conditions, the variable supporting revolving surfaceswould be modified in a suitable manner, preferably gradually, so as toobtain the maximum efficiency of the flying machine.

Preferably, the revolving system of blades is arranged in such mannerthat its revolution is always maintained through any suitable means,even when the blades are wholly or partly wound up or folded up. This isintended to ensure, under the effect of the centrifugal force, a quickunwinding or unfoldingof the Iblades under any conditions.

Preferably, the revolving movement to be maintained while the machine isflying normally is obtained by allowing a portion of the blades, whichis not folded up or wound up,. to rotate freely. This portion of theblades may be very small because the speed of self revolution of theblades increases, as the active portion of the blades is reduced. Thisoperation can be obtained with an arrangement such for instance as thatof Fig. 14 by adjusting the respective positions of nut 49 and pin 45 insuch manner that the blades, in the neutral position, are not whollyfolded up.

In Figs. 22 and 23 I have shown a flying machine including a xed wing 13and a revolving system of blades P the active length of which may bevaried.

When said blades are wholly unwound they facilitate the taking off ofthe machine, whether they turn freely, as the blades of a wind engine,or they have their revolving movement helped bycompressed air escapingfrom said blades, or they are positively driven, at least when takingoff, by the engine.

Besides the takingoif of the ying machine may take place by causing saidmachine to roll on the ground, the blades being unfolded only when themachine has moved a certain distance.

v The lift produced by the unfolding of the blades facilitates thetaking off.

The distance on which the machine runs in this case may be very smallowing to the very small resistance of the blades when folded up.Therefore the acceleration of the machine running on the ground is veryhigh. Furthermore, the lii't produced when the 'blades are unfoldedmakes it possible to take olf at a great angle and therefore from placessurrounded by" obstacles.

After taking off, the diameter of the revolving system is graduallyreduced until the speed of the machine is sufciently high for permittingit to be supported without danger by wing "I3, the

, angle of incidence of which corresponds advantageously to the bestpossible ratio of the lift and drag components. The diameter of therevolving system is then reduced to a very small value, such as ab. Thespeed of the flying machinev can thus be considerably increased, theload Aper square meter being, in this case very high, for instanceseveral hundreds of y kilogrammes. The speed of revolution of the bladesrotating freely becomes very high but as their diameter and their angleof incidence are very small, their resistance is not considerable.

If the flying machine is placed under dangerous conditions of flight,due for instance to a bad working of the engine, the release of theblades will cause them to unfold instantaneously, owing to theconsiderable centrifugal force acting thereon because of their highspeed of revolution.

If the pilot desires to reach high altitudes or to y at reduced speed hecauses the revolving system to unfold.

Also, when landing, the blades may advantageously be unfolded forbraking the movement of the machine, and if the diameter of therevolving system is sufficient, the machine will land vertically.

It should be noted that when the rotary movement of the rotor is madeuse of for producing the unfolding and the folding up of the blades, andespecially the latter operation, power is taken from the living force ofthe rotor. If the unfolding or folding operation is rapid, there is arisk of the unfolded blades stalling and oscillating with an amplitudewhich may be dangerous.

This drawback may be avoided by storing up a supplementary amount ofenergy in a fly-Wheel rigid with the rotor andturning advantageously .ata high speed owing to the provision of a suitable transmission gear. Theenergy of this flywheel may 'be used for facilitating taking off andlanding, as it will now be explained.

When starting, the blades being folded up, it is possible to cause therotor and the fly-wheel to race. When the blades are unfolded, therotor, the speed of revolution of which is reduced receives an importantportion of the energy of 'the y-wheel, and therefore keeps turning at asufficient speed. Besides, the fly-wheel keeps a sufficient reserve ofenergy for transmitting "a portion Y thereof to the rotor when theblades are folded up.

When the blades are folded up Wil/ile the machine is flying, a portionof said blades is left unfolded so as to impart a high speed ofrevolution to the y-wheel. However, if it were necessary to limit thisspeed, an automatic clutch would be provided between the iy-wheel andthe rotor, so as to cut off the connection beyond a certain speed.

According to another feature of the present invention, a flying machineis provided with at least one revolving system having blades of variableactive length, said system being so mounted on the machine that its hubmay occupy different positions, whereby it is, for instance, possible tomake use of this system either for supporting the machine or forpropelling it.

In Figs. 24 and 25 I have shown a flying machine provided withtworevolving systems of blades P, adapted to turn, preferably, in oppositedirections. These systems are disposed respectively at both ends of thestationary wing 13. Said wing may act as a support for transmissionssuch as 14, and pinions 15, which transmit the movement of the engine,preferably through a speed reducing gear to the hubs I4 of the revolvingsystems. The flying machine is then capable of taking off verticallyowing to its revolving systems of blades which are unfolded and drivenat reduced speed by the engine. of translation of the machine has becomesufficient for permitting it to be supported merely by its fixed wing(for instance after a gliding flight along an oblique path) the diameterof the revolving systems may be reduced and their hubs are inclinedhorizontally, whereby said revolving systems, which are nowadvantageously driven at higher speed, owing to the gear box, act aspropellers. y

According to another arrangement, means are provided for varying theangle of incidence of the blades, either simultaneously for all theblades and advantageously according to the diameter of the circle sweptover by saidlblades, or diierenentially. In the' rst case when therevolving systems serve to support the flying machine it is possible togive the blades the angle of incidence that is better adapted tocorrespond to the conditions of ight for taking off or landing,eithervertically or obliquely.

On the other hand when the angles of incidence of the blades are variedin a differential manner, it is possible to produce torques transmittedto the body of the flying machine, so as to permit of controlling theposition and the direction of flight of the machine, the revolvingmachines exerting, in this case, a lstabilizing action.

In order to act simultaneously on the blades, it is, for instance,possible, as shown by Fig. 20, to give blades P a thickness and aninclination which vary along their length, so that their guiding ondrums such as I6 and 23 gives said blades, due to their inclination onsaid drums, an incidence which varies according to the diameter .towhich they have been unfolded.

In particular when moving down in a vertical direction, I may provide,for the last part of the movement, a small length of the blades which isnot unfolded and which is provided with an additional thickness which isadapted to give the blades a great angle of incidence so as to transformthe kinetic energy stored up bythe revolving system into a verticallift.

In order to make it possible to control the direction and path of travelof the flying ma.- chine, according to the various conditions of flying,and especially when gliding, either vertically or obliquely, with theengine stopped, it is possible to create torques in different azimuthsby creating variations of incidence such that the maximum of incidencecorresponds to an azimuth in which it is desired to obtain a greaterlift.

However the torques transmitted to the body, of the flying .machinethrough this means are generally rather small due to the fact that theWhen the speed blades can move freely in thevertical direction under theinfluence of a greater or smaller lift.

and socket joint 18, 19 and 8|). Element 80 is guided in the hub throughgrooves.8l. A rod 82, connected with element 18 through a. ball bearing83 permits of giving disc 11 any desired inclination and also of movingupwardly or. downwardly.

By moving the plane of disc 'I1 I move the mean plane of rotation of theblades and I can therefore modify the relative position of the flyingmachine.

It should be well understood that the idea. of causing revolving systemshaving blades of variable surface to exert a stabilizing action ishereby .claimed in its most general scope and for all kinds ofaircrafts, even different from those above described, for instance forlighter-than-air aircrafts, and especially airships.

Besides, instead of acting on the incidence, I might proceed in anyother manner for obtaining the desired stabilization, for instance asfollows:

In the example 'of Figs. 24 and 25, it is possible, by differentiallyvarying the diameter of the two lateral supporting systems,'to produce atorque' capable of modifying the lateral inclination of the aircraft. Byproviding such an aircraft with a third revolving system disposed at'thefront or rear part of the fuselage it would be possible to produce avariable longitudinal torque for varying the inclination of the aircraftin the fore and aft direction thereof.

Such a system of stabilization including a plurality'of supportingsystems having blades of variable area would be particularly useful inthe case of large size aircrafts, such for instance as airships.

According to still another feature of the invention, the revolving'system of blades having a variable area is used as a parachute, thisfunction being eventually combined with one or several of those abovereferred to (sustentation, propulsion, stabilization).

For this purpose, a portion of the aircraft, preferably a portion whichcan be easily detached from the remainder of said aircraft, for instancecabin 84 (Figs. 26 and 27) is provided with a rotor having foldableblades. These blades are normally folded up in arotary hub I4, therotation of which is, for instance, maintained by the free revolution ofblades that are not folded up.

Under normal conditions of taking off, flying and landing, the rotor mayact as above described. In case of danger, the cabin can be detached,sliding along guides such as 85. Wing 13 may be out away so as to affordpassage for the elements of the revolving system when folded up.Advantageously, the cabin carries the landing gear provided forinstancewith -elastically suspended wheels 86 and with shock absorbingmeans, or it may be provided with distinct shock absorbing means.

This system of parachute may be applied to all kinds of aircrafts, andespecially lighter-'thanair aircraftsfln this case, the revolvingsystems to be used eventually as parachutes may normally serve toincrease the ascensional power of the aircraft by turning in the samemanner as a wind engine under the influence of atmospheric winds, orunder the influence of relative Wind in the case of dirigibles.

The possibility of varying the diameter ofthe blades of said revolvingsystems permits of modifying ascensional power of the aircraft withoutmaking use of ballast, which can therefore be dispensed with or reduced,so that the load carried by the airship can be considerably increased.

While I have, in the above description, disclosed what I deem to bepractical and eicient embodiments of the present invention, it should bewell understood that I do not wish to be limited thereto as there mightbe changes made in 'the arrangement, disposition and form of the partswithout departing from the principle of the present invention ascomprehended within the Z5-scope of the accompanying claims.

What I claim is:

1. A system of the type described which comprises, in combination, arotary hub and a plurality of blades carried by said hub, each bladeincluding a rigid transverse member at the free end thereof, a pluralityof cables fixed at one end to said member and at the other end to saidhub, and a supple structure associated with said cables for forming theblades, comprising an envelope associated with said system of cables,and a plastic material filling said envelope for giving it the desiredshape.

2. A system of the type described which comprises, in combination, arotary hub and a plul rality of blades carried by said hub, each bladeincluding a rigid transverse member at the free end thereof, a pluralityof cables xed at one end to said member and at the other end to saidhub, an envelope associated with said system of cables, and a fluidunder pressure inflating -said envelope for giving it the desired shape.

3. A system according to claim 2 further including means forcontinuously feeding said fluid under vpressure into said envelope, andoutlet means for allowing said fluid to escape from said envelope.

4. A system of the type described which comprises, in combination, astationary part, a hub journalled in said part, a plurality of bladessupple in the direction of theirlength adapted to slide at their innerend longitudinally in said I hub inV a direction parallel to the axisthereof,

and means for pulling said blades more or less inside said hub.

5. A system of the type described which eomprises, in combination, astationary part, a hollow hub journalled in said par@ rollers carried bythe edge of said hub in opposite diametral po- 05 sitions, twobladesmade of a common band of a supple material passing around saidrollers, so that the central portion of said band extends inside saidhub, a pulley about which said central portion of the band is wound, andmeans for moving said pulley axially inside said hub.

` 6. A system of the type described which comprises, in combination, astationary part, a. hollow hub journalled in said part, rollers carriedby the edge of said hub, a blade supple in the direction of its length,passing around each roller,

means for fixing the inner end of each blade to said stationary part, apulley in said hub around which passes the portion of said band betweenthe inner end thereof and the part that passes over said roller, andmeans for moving said pulley 5 axially inside said hub. 7. A system ofthe type described which comprises, in combination, a stationary part, ahub adapted to rotate in said part, a plurality of drums journalled onsai hub, a sleeve coaxially 10 mounted with respect to said hub androtatable with respect to both said stationary part and said hub, meansfor interconnecting the rotary movement of said sleeve with respect tosaid hub with the rotary movement of `said drums with respect 15 totheir axes, means for causing said sleeve to rotate together with saidhub, means for disconnecting said sleeve from with said hub, and

means for fixing said sleeve with respect to said stationary part. 20

8. A system according to claim 7 which further comprises, in combinationwith said means, means for automatically connecting said hub with saidsleeve so as to cause these two parts to rotate together, when apredetermined length 25 of each blade has been wound around itsrespective drum.

9. A system according to claim 7 further including manual means forcontrolling .the three last mentioned means. 30

10. A system of the type described which comprises, in combination, arotary hub, a plurality of blades supple in the direction of theirlength movably carried by said hub so as to project more or less fromsaid hub, each blade including 35 a frame work deformable in thedirection of the length of the blade but adapted to resist tensilestresses in said direction, and a hollow envelope of a uidtight matteradapted to be associated With said framework, a roller around which saido envelope passes, another roller for said framework, a fluidtight boxprovided with holes for the passage of at least one blade, said boxsurrounding the second mentioned roller, a conduit for feeding air underpressure into said box, said 45 envelope being provided with holesthrough which air under pressurevis injected into the portion of theenvelope that is located inside said box, and a band of eompressiblematerial carried by 50 said framework adapted to stop said holes whensaid framework is associated with said envelope.

11. A system of the type described which comprises, in combination, arotary hub, a plurality of blades supple in their longitudinal direction55 movably carried by said hub so as to more or less project radiallytherefrom, and a dise-shaped member rotatable together with said hubmovable in all directions with respect to the axis of said hub andengageable with the blades, so 50 -as to vary the incidence of saidblades in certain azimuths.

12. A system of the type described including, in combination, a rotaryhub and a plurality of blades carried by said hub, each blade including55 a rigid transverse member at the free end thereof,.a plurality ofcables fixed at one end to said ymember and at the other end to saidhub, a

plurality of cables extending in the transverse direction of the bladeand interconnected with 70 the first mentioned cables, for ensuring acertain rigidity of the blade in the transverse direction thereof, and asupple structure associated with said cables for forming the blade.

13. A flying machine comprising a fixed sur- 75 face sumcient alone tosustain the machine during normal flight, a motor, a rotating wing,means for selectively connecting said rotating wing to `said motor todrive said rotating wing thereby for ascent, said rotating wing beingcapable of being driven in auto-rotation when disconnected from themotor by movement of the machine through the air, means independent ofthe motor operable during flight to vary the length of said rotatingwing, and means to limit the decrease in length of saidrotating `wing sothat the same always presents a surface sufficient to maintain it inauto-rotation..

14. In a device as claimed in claim 13, means operable during flight tovary the pitch of said rotating Wing. t V

15. A flying machine comprising a fixed surface sufficient alone tosustain the machine during normal flight, a motor, a rotating wing, saidrotating wing comprising a plurality of blades of variable length and arotary member, a motor,

means Vfor selectively connecting said rotary memberto the motor, meansto vary the length of said blades,`said means being connected to saidrotary member so as to be actuatedby the latter independently of saidmotor, whereby the energy necessary to extend or to Withdraw the bladesduring flight is taken from the kinetic energy of said rotary member,and means to limit the withdrawal of the blades so that the latterpresent, in their neutral position, a sufficient aerodynamic surface toassure their rotation by the relative wind during flight. y

16. In a machinel according to claim 15, a ily wheel connected to saidrotary member.

17. In a `machine according to claim 15, independent stabilizing meanson the stationary wing and on the rotating wing respectively.

18. A flying machine comprising a stationary wing and at least onerotating wing, said rotating wing having blades, means to vary theeffective surfaces of said blades, and means to limit the action of saidlast means so as to maintain at all times a portion of the surfaces ofsaid bladesl effective of suicient area that during flight said rotatingwing is always maintained in rotation, said machine having a portioncapable of being released from the remainder of the machine, saidrotating wing being lconnected to said lreleasable. portion to `act as a`parachute therefor.

19. In a flying machine comprising at least one fixed aerodynamicsurface capable, with a forward drive propelling system, of sustainingthe machine in normal flight under conditions approximating the optimumratio between the lift and drag components, the combination of aflexible extensible rotatable wing capable of addl ing its own lift tothat of the fixed aerodynamic G0 surface for ascent and for landing,andmeans for regulating, at least partially, the flexibility thereofduring normal flight and the extension thereof for ascent and landing.

20. In a flying machine comprising lat least one xed aerodynamic surfacecapable, with a forward drive propelling system, of sustaining themachine in flight, a rotatable wing system with wings having a flexiblepart and a rigid part, the rigid part being sufficient to maintain saidwing system in rotation, and means for regulating, at least partially,the exibility of said wings during normal flight and extension thereoffor ascent and landing.

21. In a flying. machine comprisingat least 75 one fixed aerodynamicsurface capable, with a forward drive propelling system, of sustaining jthe machine in normal flight, in combination, a

for controlling the flexibility of said wings for normal flight and forextending the same for ascent and landing, said last named means beingconnected with the lifting system so as to obtain therefrom kineticenergy for extending or retracting said Wings.

23. An aircraft supporting rotor 4vane consisting of a hub; of multipleair tight envelopes, fabricated to airfoil rotor shape, reinforced toresist centrifugal and lifting stresses the open ends of the envelopesbeing adapted and arlranged to be attached at a positive angle ofincidence to the hub which rotates when in action; and means to inflatethe envelopes while so attached and while in action.

, 24, Horizontal safety rotors for aircraft comprising in combination,furled packs of multiple bladed pneumatic reinforced rotors adapted andarranged to loweror land aircraft; means to rotate the rotor-bladepacks; and means to unfurl the rotor-blade packs and inflate therotorblades while they are rotating.

25,. An aircraft supporting rotor comprising inv combination arotor-head provided with flexible pneumatic rotor-blades; weighted meansfixed to the inflated rotor-blades to produce by means of centrifugalforce the proper rigidity and shape when the rotors are in circularmotion.

26. The combination of an aircraft supporting rotor; with resilientpliable pneumatic rotorblades adapted and arranged to be furled into apack and concealed when not in use and means to unfurl and inflate whenin use.

27. An aircraft supporting rotor vane comprising in4 combination arotor-shaft, a rotor-head with multiple flexible pneumatic lrotor-bladesfixed to the rotor-shaft; the rotor-blades adapted and arranged forsupport of the aircraft; and means to deflate and furl the rotor-bladesinto a rotor-pack while the rotor blade pack, the

rotor-head and rotor-shaft are rotating. 'l

a hub; of multiple collapsible rotor blades flxed to the hub at apositive angle of incidence adapted and arranged to rotate when inaction while the rotor blades are collapsed; and means to release andproject the rotor blades from the hub after the hub is rotating. i

30. An aircraft supporting rotor pack consisting of a hub, of multipleflexible rotor blades fixed to and collapsed around the hub; means torotate the hub and rotor blade pack while collapsed; and means torelease and project the collapsed rotor blades from the hub while thehub and rotor blades are rotating.

31. A horizontal flexible aircraft rotor, consisting 0f a hub with a.resilient pneumatic rotor blades adapted and arranged for vertical liftwhile taking oi or landing; and cable means attached to the rotor bladesfor rolling the rotor ,blades into a rotor pack while the rotor is inthe rotor blades, cooperating with rotor blade furling means attached tothe rotor head, for rolling the rotor blades into a rotor pack.

33. A rotor shaft; a rotor sleeve; a rotor pack consisting of multiplefurled rotor blades; means to operate the rotor shaft and rotor sleeveat the same speed while the rotor is unfurled and :rotating; means forreducing the speed of the rotor sleeve in relation to the speed of therotor shaft for furling the rotor blades; and means to rotate the rotorsleeve at a. faster speed than the rotor shaft While the rotor bladesare being unfurled.

34. A hollow rotor shaft; a rotor head with multiple pneumatic rotorblades rolled inside a rotor pack xed to the hollow rotor shaft, air orgas supply connected to the hollow rotor shaft;

and means for injecting air or gas into the furled rotor blade packthrough the hollow rotor shaft, while the hollow rotor shaft, the rotorhead and rotor pack are rotating andthe rotor blades are unfurling fromthe rotor pack.

` to unfurl the rotor pack into rotor blades after the rotor shaft,rotor head and rotor pack are rotating; and means to inflate the rotorblades while the rotor blade pack is rotating and being unfurled.

36. An aircraft supporting rotor vane. comprising in combination, arotor shaft, a rotor head with multiple exible pneumatic rotor-- blades,xed to the rotor shaft; the rotorlblades while in circular motionadapted and arranged for support of the aircraft; and means to deflateand furl the rotor blades into a rotor pack, while the rotor blade pack,the rotor head and rotor shaft are rotating.

37. An aircraft rotor vane consisting of a rotor head with multiplepneumatic rotor blades; cable furling and centrifugal weight means ixednear the outer tips'of the rotor blades, used for the dual purpose offurling the rotor blades and placing the desired weight for centrifugalpull near the outer ends of the rotor blades while they are unfurled.

RAUL PATERAS PESCARA.

